[asterisk-users] SPA3k wired to PAP2 for echo testing

[Stephen Davies]

On 05/11/06, James Harper <james.harper at bendigoit.com.au> wrote:
> Even in this configuration, with my impedance settings set to the
> Australian standard of 220+820||120nf, and the PSTN and PAP2 echo
> cancellers enabled (or not, and all combinations of) I get local echo as
> soon as I pick up the handset (I hear my voice bounced back to me).
> Surely this shouldn't be??? There is no hybrid involved at all!

'course there is. The telephone interface on the one end and the line
interface on the other are both 2 wire.

Did you have a phone line connected to the "other side". Running into
an unconnected FXO port is likely to make echo because of the
unbalanced impedance.

Steve